Visualizing COVID-19 Data in Miami-Dade County

Roy Williams, Mary Jo Trepka, Zoran Bursac, and Gabriel J. Odom

DISCLAIMER: all data is from the Florida Department of Health unless otherwise stated

COVID-19 is a highly contagious respiratory infection caused by the novel coronavirus SARS-Cov-2
The incubation period is 2-14 days, so observed data lags community transmission 1-2 weeks
The South Florida (SFL) metropolitan region is comprised of Miami-Dade, Broward, and Palm Beach counties
There are roughly 6.4 million people in these three counties (30% of the state’s total population)
As of today, Florida has had 2.7 million COVID-19 cases (1 million in SFL) and 39965 deaths (12434 in SFL) since March 5, 2020

First Wave: Early March (second week) to mid-May 2020
Second Wave: Mid-June through August 2020
Third Wave: Late October 2020 through 2021 “Spring Break” Season and ending in May 2021
Fourth Wave: Mid-July 2021 to current (shown later)

March 16, 2020: confirmed “Patient Zero” in Miami-Dade
March 28, 2020: Gov. DeSantis issues a “Safer at Home” order (a lockdown) effective April 1st and required all hospitals to report their COVID-19 data to the state daily
Early April 2020: representatives for local elected officials reached out to us for help understanding trends in the data they were receiving daily (example report excerpt below)

In mid-April 2020, the White House released reopening guidelines based on 14-day trends in testing, positivity rates, and hospital capacity (Note: at this point, the state of the science was that SARS-Cov-2 was primarily spread via surface contact)
The 14-day trend of case counts and test positivity rates became negative in early May, and hospitals had sufficient capacity
On May 18, 2020, Miami-Dade County lifted the lockdown restrictions

“Nothing could be older than the daily news, nothing deader than yesterday’s newspaper.” - Edward Abbey

At the end of the spring school semesters and after the Memorial Day holiday (May 25), cases began to rise
The Florida Department of Health (FLDoH) reported testing data for the most recent 14 days only (below)
Local elected and administrative officials struggled to interpret this data, lacking context necessary to compare to the First Wave

Using our figures, local officials were better able to contextualize the current state of affairs in the county than they had been using the tables/figures reported by the state Department of Health
A “Mask in Public” ordinance had been in place since the end of May, but it was not enforced
On July 2, 2020, city officials began enforcement of that ordinance
Note 1: Because of the viral incubation period, “current” testing data and hospitalization data was already too old to measure the current state of community transmission
Note 2: the county did not lock down because “deaths were decreasing” (more on that next)

During the rapid rise of COVID-19 cases and hospitalizations, some of the officials we met with noticed that the number of COVID-19 deaths reported by the state was decreasing, while the number of patients reported to be on ventilators in the hospital was increasing
Based on the medical experience at the time, we expected 80% of ventilated patients to expire

Was this because COVID-19 was no longer a threat?

NO!

The grey columns are the reported COVID-19 deaths for March-June, 2020, as reported on July 1, 2020
The other stacked columns show how the counts for the exact same days will increase over time as more deaths are reported and certified
Using this figure, we convinced the local officials that daily death counts were completely inappropriate data to use in making health policy decisions
The local offices of the health department informed us that that medical examiners offices were hopelessly backlogged (Florida required at that time for all COVID-19 deaths to be certified by a medical examiner; this policy changed in August)

We no longer have 2-3 month delays in death reporting; this “lag” is 1-3 weeks now, and we have a better understanding of the implications of this delay
However, even in 2021, these same shoddy and misinterpreted data are still being used to erroneously claim that the Delta variant “isn’t that bad”

We were blessed to have local officials who cared about science, and we were lucky to be able to work with an incredible interdisciplinary team of experts
Real data is messy
Responding to a pandemic is exhausting–our team worked 7 days a week for months on end
Even very smart people can make bad decisions when data are displayed poorly
“Hindsight is 20/20”
We, and all of the people we worked with, made mistakes
Consider a modification of Hanlon’s Razor: “don’t attribute to malice what can adequately be explained by inexperience, underfunding, and exhaustion.”

Our paper is here (it’s open access)
The emergency order giving us access to the data expired in June 2021, so we have not had access to state data
We have access to similar data from the CDC, but they use a different data dictionary
We are in the process of reverse-engineering the state health department data from the CDC data in order to have an “apples to apples” comparison across the entire pandemic

Please get vaccinated!